Quality of winter soft wheat grain under the influence of repeated and intermediate sowing in cotton-grain rotation

. Research work was carried out in 2017-2020 in a system of cotton-grain crop rotation on light gray soils of the Kashkadarya region of the Republic of Uzbekistan. This article describes the results of the positive effect of root and crop residues of mash and corn sown as repeat crops, as well as the sowing of intermediate crops of perco, rye as a green fertilizer in the soil on the quality of soft wheat grain in the crop rotation system.Grain quality improved due to the impact of a re-crop of mung bean sown after winter wheat and an intercrop of perco in a cotton-grain rotation system. Qualitative indicators of grain from year to year decreased as a result of the chronic sowing of wheat.


Introduction
The efficiency of wheat production is related not only to gross production but also to qualitative indicators, which depend on the price and market competitiveness of the output. Meteorological conditions, soil fertility, applied agrotechnological measures, biological features of the variety affect the quality indicators of winter wheat grain. The above factors can be divided into two groups, the first being uncontrollable factors (weather and climatic conditions during the growing season) and the second-managed factors (plant nutrition, protection against weeds, diseases, pests). At the same time, one of the main factors is the increase in grain yield and the quality of winter wheat in the future due to the preservation and improvement of soil fertility.
According to scientists, the yield and quality of wheat grain depend on the influence of the external environment, agrotechnical measures, plant species. Chronic grain treatment leads to an increase in weeds, pests and diseases. This necessitates the use of a large amount of pesticides, which in turn leads to a significant increase in the cost of production. Further impacts include negative changes in the soil, including a decrease in organic matter, carbon and total nitrogen. Scientists also note that the influence of root residues on soil fertility can be much higher than in other organic fertilizers. The Russian scientist Chibis notes that with incorrect crop rotation and chronic processing, the soil is subject to severe degradation, as a result of which yield and quality are reduced.
In studies carried out by the Russian scientist Tikhonov, after 2 years of growing wiki+white mustard and alfalfa as a siderat, the quality of gluten improved in the cultivation of winter wheat compared to the control option (pure plow) аnd the highest result was the gluten quality of 2-yearold alfalfa seeding, that is, IDK 77.5 which is defined as сlass 2 (good). In studies conducted by Somova the amount of protein was 17.0%, and the amount of gluten was 34.0% when using rapeseed seeds as siderata in the spring wheat rotation system in the northern region of Kazakhstan. In works show that the quality of winter wheat grain is strongly influenced by previous crops, which affects its cost. According to their data, the protein and gluten content of grain is high when winter wheat is cultivated after buckwheat and soybean, protein content is 12.4-13.3%, gluten is 23.5-27.9%, and when sowing chronic winter wheat is 9.2-9.6%, gluten is low-17.5-17.8%. In a similar study Wozniak reported that the production of winter wheat in the monoculture system resulted in a 10% reduction in the mass of 1000 grains, a 4.7% decrease in the gluten content and a 32% decrease in yield compared to the system of crop rotation. In the article "Yield and quality of wheat in crop rotation in the southern forest steppe of Western Siberia" in the system of rapeseed and soy rotation influence the technological indicators of grain quality, рrotein in soybean cultivation increased by 6.7% compared to rapeseed and gluten by 8.4%. It has been noted that this depends on the nitrogen enrichment of soybean as a precursor crop.
In the experiments a favorable precursor crop for wheat yielded a high yield when sowing in a mixture ofmash, perco+ rapes. Due to favorable precursors, the protein content in grains increased by 2.0-2.1%, gluten by 0.8-1.1%. In Dzhizak desert experience, when sowing cotton and winter wheat after mash, grain content was 15.1% or 0.88 t/ha protein, 28.1% or 1.8 t/ha gluten, t.k and 68.4 kg/ha feed unit and 6.8 kg/ha protein digestion. In the experiment, it was studied that as a result of crop rotation cotton-wheat, alfalfa-wheat, soybean-wheat, protein content after soybean 0.2%, after alfalfa 0.9%, gluten content increased by 0.9-3.1%. In the experiments of Oripov in winter wheat production after mash and rapeseed the quality of grain improved, the quality of grain was 18-33 g/l, the mass of 1000 grains-2.9-3.6 g, the protein content 2.0-2.1% the amount of gluten was above 1.1-1.2%. This pattern has also been observed in our experiments, and it has been observed that the technological quality of wheat grain has improved as a result of the impact of repeated and intermediate crops, They are planted after winter wheat in systems of rotation of winter wheat crops and absence of sowing of any crop. sowing and intermediate crops after winter wheat.

Experiment scheme
Research work was carried out in 2017-2020 in a system of cotton-grain crop rotation on light gray soils of the Kashkadarya region of the Republic of Uzbekistan.
The field experience was conducted on a total area of 0.79 hectares, the area of each plot is 180 m 2 , the number of options 11, and the number of replacements 4 in time and space. Our research was conducted according to generally accepted recommendations and guidelines (Table 1). The quality of winter soft wheat was studied in a system of cotton-grain crop rotation as a result of repeated and intermediate crops after winter wheat.

Methods for determining the quality indicators of winter wheat grain
To determine the quality of soft wheat seeds collected from the field, samples are taken from each variant and repetition following the requirements of GOST 13586.

Results and Discussion
One of the most important indicators that determine the grain quality of winter soft wheat varieties grown in various soil and climatic conditions of our republic is hectoliter, which determines the fullness of grain and flour yield. Accordingly, the nature of grain is included in the list of state standards as one of the indicators that determine its grain quality.
Grain nature is a certain volume of purified grain mass, brought to the basic state, and its volumetric mass is expressed in g/l (GOST 10840-64, 2009).
According to the data obtained in the first year of research (2018), it was noted that the hectoliter weight of the experimental variants was 777.8-785.  Figure 1). These grain indicators in 2020 due to the influence of re-sowing mung bean and catch crops (cotton (C); wheat + mash + perco; cotton (WMP; C) and cotton C; wheat + mash + rye; cotton WMR; C) are 790.7-788.0 g/l, under the influence of repeated sowing of corn and intermediate sowing of perco and rye (cotton; wheat + corn + perco; cotton (C; WCrP; C) and cotton; wheat + corn + rye; cotton (C; WCrR; C)) amounted to 787.2-785.6 g/l.  Bread from wheat flour is a unique food product, its chemical composition depends on its beautiful appearance, softness, good taste, nutritional value, and good digestibility in the human body. The amount of protein and gluten in grains is one of the main indicators of grain quality.
In our experiments, the influence of repeated and intermediate crops on crop rotation affected the amount of protein and gluten in winter soft wheat in different ways in 2019-2020 ( Table 2).
The smallest amount of protein (13.0%; 12.4%) and gluten (25.3%; 23.8%) in the grain was observed in the variant where wheat was sown instead of wheat. It was determined that the protein content (2019) was 13.5%, and the gluten content was 25.8% in the variant without sowing repeated and intermediate crops from winter wheat ( Table 2).  (Table 2).
In our studies, when we analyzed the results of gluten quality, that is, the IDK index, from the studied options in the cotton-grain crop rotation system, it was found that in option 3, where wheat was planted every year, the gluten quality corresponded to class III, and in the rest options II class. It should be noted that due to the impact of a repeated culture of mung bean sown after winter wheat andinter-mediate culture perco, the quality of gluten improved from year to year and met the requirement of class I. In particular, the final effect of the re-culture of mung bean and

Conclusion
In the cotton-grain crop rotation, the quality indicators of grain are improved due to the impact of the repeated crop of mung bean sown after winter wheat and the intermediate crop of perco, as a result of field weed control during chronic wheat care, grain quality indicators decreased year after year.
To grow a high-quality crop of winter wheat in the conditions of irrigated light gray soils of the Kashkadarya region, sowing after winter wheat, re-sowing mung bean and intermediate sowing perco or rye, and in spring plowing with green manure will have a positive effect on improving the quality of the grain, quality grain of the 1st grade was obtained with a protein content of 14.6-15.5%, gluten 28.2-29.1%, IDK 75.0-75,3.